Hello,

Can true headspace be determined when a case is only fired once in the chamber of the same rifle? I've heard that it may take 2 or 3 firings before the headspace of a case can be accurately measured to the chamber. If that is a true statement, can I use the Hornady Neck Sizing Die to just neck size the first few fired cases while waiting for "true" chamber headspace to be reached then use the dies full potential to neck size and bump the shoulder as needed?

Any input is greatly appreciated.

Thanks
Mike

something to consider:
Headspace is defined as the space or distance between the face of the bolt and a specific predetermined point in or at the chamber. For bottlenecked rimless cartridges like the 30-06, headspace is measured from a point on the chamber's shoulder to the bolt face.
The brass case has shrinkage and I don't think it gives a true measurement.
Some reloaders refere to it as head space.
Regardless of how loads fit your chamber, handloads should always have minimum shoulder clearance. Most reloaders commonly refer to chamber clearance as "headspace". However, the term "headspace" actually makes things a bit confusing for some people. For handloading purposes, the term headspace means any chamber clearance that allows your cartridge to move or expand forward or rearward..

One time firing should expand the brass to its full potential in your chamber, this once fired should be a duplicate of the chamber UNLESS these are anemic loads of some variety.

This subject is, by far, the most misunderstood, and mis-spoken about, topic ever to be discussed among shooters.
"True" headspace, meaning a dimension, including tolerances, of a chamber, can ONLY be measured with gauge; not a piece of brass. Brass is so ductile (has to be to do it's job) that it almost never shows the real condition of your chamber. I can make a piece of brass show anything you want. Hand loaders do our best, to minimize the extra distance from the bolt face to the cartridge head. You are right to try to minimize that.
Probably, we should use only rimmed cartridges, so as to avoid all the drama. Not belted; more potential drama.

volumes can, and have been, said here on the subject.

in short, NO -- you can't measure headspace from a fired cart --as headspace measures face to datum OF the firearm.

can you set cases to a uniform dimension from measured fired cases? sure can -- and it's marketed as headspace, but this is like calling a liter a mile ... you aren't measuring the same things

OH NO...Mr. Bill...pleas don't start this thing up again...DP and JEFFE said it right and so has MILLIONS of others...PLEASE...do a search here on AR AND on the 'net AND Wiki...this subject has been covered by experts and even they get tied up in rhetoric and verbiage and with all the various ways manufacturers have measured headspace even a simple definition just isn't really simple at all.

It's a VERY GOOD QUESTION, but the answer can give you an EXCEDRIN headache.

You want to go nutz...just measure a few different brands of belted cases...they run from <0.200" to OVER 0.225" with 0.220" as being the SAAMI spec. No wonder belted mag cases have a short life.

I agree rimmed cases are MUCH easier to "Headspace"????

Good Hunting

Yeah, we just went through this same topic last week.
Just FI, belted brass and ammo tolerance between max chambers and min brass is .018, SAAMI spec. And as NON said, in actuality, brass is made very sloppily. Most shooters would have a conniption fit it they knew it was the much, thinking that Eighteen Thousandths of "space" will cause their rifle to detonate. It won't.
Just try to make your brass fit your chamber as well as possible.
There are right ways to do that, and wrong ways. Do some searching here and you will see both ways.

One of the very good reasons for the various brands of rifles that use a nut to set headspace.

Buy a couple hundred cases of your favorite brand...use one case as a dummy to set the headspace, MARK that one and set aside...THEN...after you've had the headspace set by a gunsmith or yourself, if you feel comfortable doing so, from then on "headspace on the case shoulder and adjust your sizer to match.

Been doing it that way for umpteen years and even do it somewhat that way on my "nutless" rifles when I build a belted mag I have gone 20 times reloading one case with a top load and 300 gr bullets in my 375 H&H...which is a case stretcher to say the least...just to see "what's the Hap's"

Belted Mag and "EZY" headspacing is another of those "big lies" foisted on an unsuspecting populace that very few ever understood unless they were gunsmiths and learned the trade well. Much of that "older, secret knowledge" is lost on todays crop of 'smiths and on the general public as well...plus the 'net doesn't always provide good information/reference material.


OIT here in Oregon closed out it's gunsmithing program and I just talked to a gunstore owner that said Trinity Collage in Susanville, KAlIF is being threatened by some of the newer anti-gun laws, more or less indirectly.

Anyway, it's a sticky subject.

Good Hunting

While I understand what headspace measurement is technically I prefer to stick to plain English and the practical application for the rifleman. Headspace is simply the space left between the breech face of any firearm and the head of the cartridge when the action is closed (head space). Note I didn't say the measurement, I said the space.

The idea in reloading is to use the opportunity if available depending on the type of case, to set sizing dies to minimise this space to prevent case stretching when the cartridge is fired. Some firearms such as the SMLE in 303 British (a rimmed case), had interchangeable bolt heads to eliminate or minimise the head space with factory ammo.

It doesn't really matter what the true technical definition is, for the rifleman who are seeking good performance and good case life minimising this little space is the aim of the game and you don't need any fancy measuring equipment to do so.

Brilliantly put.

Just think - solution. What do I need to do & how.

Look at this. https://www.youtube.com/watch?v=DCxQJZ376gY

I wish this was around 25 years ago when I started reloading.

Now all my ammo is a perfect fit with no issues of tight bolt closing (a result of improper partial full length sizing that pushes the shoulder forward). I can repeat my loads batch after batch after several years.

I think my ammo is also more accurate - with virtually no really poor groups. How much is due to this gadget is not clear.

quote:

Originally posted by eagle27:
While I understand what headspace measurement is technically I prefer to stick to plain English and the practical application for the rifleman. Headspace is simply the space left between the breech face of any firearm and the head of the cartridge when the action is closed (head space). Note I didn't say the measurement, I said the space.

The idea in reloading is to use the opportunity if available depending on the type of case, to set sizing dies to minimise this space to prevent case stretching when the cartridge is fired. Some firearms such as the SMLE in 303 British (a rimmed case), had interchangeable bolt heads to eliminate or minimise the head space with factory ammo.

It doesn't really matter what the true technical definition is, for the rifleman who are seeking good performance and good case life minimising this little space is the aim of the game and you don't need any fancy measuring equipment to do so.

No, the extra distance between the case head and the bolt head is NOT headspace, and to say that just confuses everyone else who is not clear on it. Which is why the very subject is widely mis understood among shooters and reloads.
Of course the goal is to minimize that gap, even if it does not have a name. Which it doesn't.

With the proper instrumentation, you can measure headspace on a fired cartridge. However, due to a certain amount of resilience in the brass the measurement is going to be a little short; likely on the order of a thou or so. More than that if the brass is hard and the pressure low. A telescoping gauge is a better way to measure chamber headspace.
By the way, the proper term for the distance between the head of the case and the breech face is, as I understand it, "head clearance". For what it's worth. Regards, Bill

quote:

Originally posted by dpcd:
No, the extra distance between the case head and the bolt head is NOT headspace, and to say that just confuses everyone else who is not clear on it. Which is why the very subject is widely mis understood among shooters and reloads.
Of course the goal is to minimize that gap, even if it does not have a name. Which it doesn't.

I did qualify my post that I was using plain English and not the correct technical definition. At least we all seem to agree that it is that space/gap/clearance and any other plain English name that describes a gap between one surface and another that we are trying to minimize to help with accuracy and preserve case life.
Bottleneck, belted, rimmed and rimless straight wall cases all use different 'parts' of the chamber to attain headspace but in all cases it is that breech face/boltface to cartridge head gap that we are working on. Anything else confuses the issue.

With break open firearms that have developed too much headspace, work on the hinge pin or side cams will restore headspace without doing anything with the chambers or cartridge cases, but again it is that little gap we work on.

The term often used is "excessive head space".

[Edited] Let me clarify If the chamber / bolt gun are to spec, the the space is the tolerance. If it is more than spec and out of tolerance, then it is excessive head space.

It is used in reference to a bolt lug / recess set back that results in the shoulder of the case not resting firm against the chamber & therefore stretching.

In other words, the space between the bolt face and the chamber shoulder is excessive - more than standard specified.

quote:

Originally posted by dpcd:
No, the extra distance between the case head and the bolt head is NOT headspace, and to say that just confuses everyone else who is not clear on it. Which is why the very subject is widely mis understood among shooters and reloads.
Of course the goal is to minimize that gap, even if it does not have a name. Which it doesn't.

AGAIN...HEADSPACE IS A TECHNICAL TERM DEFINED IN A SPECIFIC WAY FOR VARIOUS CARTRIDGES...GO TO SAAMI to read the definition.

HERE IT IS.

HEAD CLEARANCE..."The distance between the HEAD of a fully seated cartridge or shell and the FACE of the breach bolt when the action is in the closed position. COMMONLY CONFUSED WITH HEADSPACE."

HEADSPACE..."The distance from the face of the CLOSED BREACH of a firearm to the SURFACE IN THE CHAMBER on which the cartridge case SEATS"...aka THE DATUM LINE.

Want to see a picture...take a look at the SAMMI drawing of ANY CARTRIDGE AND READ THE FINE PRINT. I have one for the 26/28 Nosler in front of me now in my load data folder for those cartridges.

In the notes the symbol of an x in a circle designating HEADSPACE is shown in the CHAMBER drawing as "2.2390" from the BREACH FACE to a point on the shoulder (about half way between the shoulder and neck junctions) AT 0.420" B FOR BASIC".

2.3308" is the HEADSPACE designation for the CARTRIDGE...AND
2.2390" is the HEADSPACE designation for the CHAMBER...

AS DEFINED by SAAMI.


The picture of the CARTRIDGE drawing(note one is the CHAMBER one is the CARTRIDGE) is 2.3308" at 0.420" B... 0.0918" DIFFERENCE...THIS COULD BE CONSTRUED AS HEAD CLEARANCE the distance from the closed bolt face to the cartridge base...


If WE ALL would just refer that question to SAAMI definitions, this DIS-INFORMATIONAL roundy-roundy would soon be finished and EVERYONE would understand the actual concepts between HEADSPACE and HEAD CLEARANCE.

WE ALL seem to know and understand what HEAD CLEARANCE is and what to do about it...but I guarantee very few seem to be able to keep the actual definitions separated even tho' we might know what they are in our minds.

Good Hunting

Only AR members are even concerned with either dimension or definition, correct or not. 99% of average hunters neither know, nor care, what his headspace, or head clearance is. And he doesn't need to know or care.
Maybe a few others out there.

Your head clearance of a sized case is equal to the amount of shoulder bump minus any brass springback. With a neck sized only case the head clearance decreases to zero after a few firings and you will feel resistance closing the bolt.

On a full length resized case for a bolt action you want .001 to .002 head clearance. And for a semi-auto you want .003 to .006 head clearance.



Below is a animated image of a rimmed .303 British cartridge being fired in a Enfield military chamber. And at max military headspace of .074 and a rim thickness of .058 you would have .016 head clearance. And this would cause case head separations in just a few reloads.



Below measuring a "fired" case with a Hornady cartridge case headspace gauge. Then the die is adjusted for the proper amount of shoulder bump.



There will be slight brass spring back of the shoulder location when measuring a fired case. And this depends on the brass hardness and annealing.

Bottom line with the Hornady case gauge there is no guessing. And you simply bump the shoulder back .001 to .002. And no need to use "feel" when chambering a sized case to see if the shoulder has been bumped back far enough.

quote:

Originally posted by eagle27:
While I understand what headspace measurement is technically I prefer to stick to plain English and the practical application for the rifleman. Headspace is simply the space left between the breech face of any firearm and the head of the cartridge when the action is closed (head space).

nope -- headspace, technicaly,
has NOTHING to do with a cartridge in the breech or not -- it is the length from the face (bolt or breech) to the datum -

quote:

Originally posted by eagle27:

Note I didn't say the measurement, I said the space.

this isn't headspace - so if you wish to use "plain english" then make up a word for it ..
as even a FIRED cart doesn't have this dimension for more than an instant (physics definition of instant, not common use)

quote:

Originally posted by eagle27:

The idea in reloading is to use the opportunity if available depending on the type of case, to set sizing dies to minimise this space to prevent case stretching when the cartridge is fired.

Some firearms such as the SMLE in 303 British (a rimmed case), had interchangeable bolt heads to eliminate or minimise the head space with factory ammo.

ah, nope -- ANY round that is both fired and extracted is SMALLER than this "plain english"
measurement ..

quote:

Originally posted by eagle27:

It doesn't really matter what the true technical definition is,

yes, it does ... exactly like trying to use "fuel" in your car, when you introduce diesel into a petro car, there is a problem ..
doesn't matter than one calls it "fuel"
.. wrong is wrong

quote:

Originally posted by eagle27:

for the rifleman

headpsace isn't just rifles -

quote:

Originally posted by eagle27:

who are seeking good performance and good case life minimising this little space is the aim of the game and you don't need any fancy measuring equipment to do so.

Everything you said is covered by necksizing - and has been published as such, for decades -

quote:

Originally posted by NONAGONAGIN:
AGAIN...HEADSPACE IS A TECHNICAL TERM DEFINED IN A SPECIFIC WAY FOR VARIOUS CARTRIDGES...GO TO SAAMI to read the definition.

HERE IT IS.

HEAD CLEARANCE..."The distance between the HEAD of a fully seated cartridge or shell and the FACE of the breach bolt when the action is in the closed position. COMMONLY CONFUSED WITH HEADSPACE."

thank you!
for here on, we should shun ANYONE that uses "head space" to the confusion of clearance .

quote:

Originally posted by jeffeosso:

quote:

Originally posted by eagle27:
While I understand what headspace measurement is technically I prefer to stick to plain English and the practical application for the rifleman. Headspace is simply the space left between the breech face of any firearm and the head of the cartridge when the action is closed (head space).

nope -- headspace, technicaly,
has NOTHING to do with a cartridge in the breech or not -- it is the length from the face (bolt or breech) to the datum -

quote:

Originally posted by eagle27:

Note I didn't say the measurement, I said the space.

this isn't headspace - so if you wish to use "plain english" then make up a word for it ..
as even a FIRED cart doesn't have this dimension for more than an instant (physics definition of instant, not common use)

quote:

Originally posted by eagle27:

The idea in reloading is to use the opportunity if available depending on the type of case, to set sizing dies to minimise this space to prevent case stretching when the cartridge is fired.

Some firearms such as the SMLE in 303 British (a rimmed case), had interchangeable bolt heads to eliminate or minimise the head space with factory ammo.

ah, nope -- ANY round that is both fired and extracted is SMALLER than this "plain english"
measurement ..

quote:

Originally posted by eagle27:

It doesn't really matter what the true technical definition is,

yes, it does ... exactly like trying to use "fuel" in your car, when you introduce diesel into a petro car, there is a problem ..
doesn't matter than one calls it "fuel"
.. wrong is wrong

quote:

Originally posted by eagle27:

for the rifleman

headpsace isn't just rifles -

quote:

Originally posted by eagle27:

who are seeking good performance and good case life minimising this little space is the aim of the game and you don't need any fancy measuring equipment to do so.

Everything you said is covered by necksizing - and has been published as such, for decades -

Ah so you can take out any headspace in a 458 Win Mag chamber by necksizing, Hmmmm yes? There are even some bottle neck cases where necksizing doesn't work if trying to minimise headspace.

I do repeat I am not disputing the technical aspects of the term headspace but in plain English, for those that speak it, headspace manifests itself and can be simply viewed as the space/gap/clearance between a cartridge case head and the breach/bolt face and this is what the focus is on trying to minimise. Gee how many of us have checked for excessive "headspace" by sticking circles of aluminium foil on the bolt face until we get a snug fit, we don't stick it on the bloody case shoulder. Why were different bolt heads made available for the SMLE, they didn't make cartridges with thicker or thinner heads or push out the shoulders on batches of cartridges to reduce headspace, they just changed the bolt head to take up the space. What happens when a break open gun goes off the face, how the headspace is technically measured doesn't matter diddly squat, the gun has to be brought back on face, nothing to do with the chamber dimensions or cartridge. That little gap that has developed between the barrels/cartridge head and breech face has to be taken out.

Why do you think there is so much confusion over the term headspace? Because some go into so much detail of it being measured from a datum point in the chamber or on the case and when the cartridge is fired it expands and contracts and blah blah blah blah while the poor tyro gun owner and reloader scratches his head and wonders what the hell language you are speaking. Just think head - space/gap/clearance/foil thickness/blade of grass stuck on breech face, piece of brass stuck on bolt face, broken finger nail in breech, anything but not datum bloody points

Shun...NO...GET A ROPE...YES...

EVEN WITH A DIRECT QUOTE FROM SAAMI, the "stuff" DOESN'T stop...the need to be RIGHT, OUTWEIGHS a dirty fact...Go Figure.

Now for another nasty fact ready for combat...I use a new, sized in the sizing die I will be using, piece of brass to set ZERO HEADSPACE on SAVAGE nut jobs and leave ~0.007" +/- 0.002" bolt head clearance from the barrels end and get as close to that as I can get for no-nut jobs...forget the BS about brass being crushed...if you're a gunsmith and cant feel when the bolt closes on a case you need practice. If I miss(now and then) I just grind what is required off the base of the sizer, take a bit off the barrel end or shoulder OR use a Redding Comp shell holder...pretty simple and NO dust ups over minutia that doesn't matter. Even with minor hiccups a go gauge will still go.

Besides...with all this jumping around I haven't read ANYTHING about the fact that SAAMI headspace has a built in tolerance when looking at a CHAMBER drawing and a CARTRIDGE drawing...other than the number I mentioned...so in reality NO ONE REALLY CARES about facts only proving their point, right or wrong...pretty much humans as usual.


As DP keeps saying...only AR members(or other anally retentive people like benchresters/longrangers/targeteers and me ) and gunsmiths go nuts over minutia and beat the poor beast to death.

Good Hunting

So we all agree headspace is the thickness of a fingernail

quote:

Originally posted by eagle27:
Ah so you can take out any headspace in a 458 Win Mag chamber by necksizing, Hmmmm yes?

head clearance -- but i'll take this as if we are having a warm, but friendly,
conversation, and ask that you read this,
not as someone pounding on you, but to try an clarify --- let me make this perfectly clear,
headspace is a measurement of the firearm -
of an EMPTY chamber, that doesn't actually matter if brass even exists - it is NOT a measurement of brass .. please do take this from someone that's designed carts -- chamber reamers and reloading dies have different measurements -
and brass has a third set -- brass is meant to be smaller than the chamber -- i think we can agree on this, as brass larger won't(usually)
fit ..

quote:

Originally posted by eagle27:

There are even some bottle neck cases where necksizing doesn't work if trying to minimise headspace.

headspace is set, brass is variable -
continuing to use the term leads to confusion.

quote:

Originally posted by eagle27:
I do repeat I am not disputing the technical aspects of the term headspace but in plain English, for those that speak it, headspace manifests itself

this is where we fork - you keepaying of the cartridge - in as plain of english as I can master, headspace is measure on an EMPTY firearm (well, one could say the gauge is a thing, so, empty of a case) - and trying to bend this is the confusing part

quote:

Originally posted by eagle27:

and can be simply viewed as the space/gap/clearance between a cartridge case head and the breach/bolt face

it can be considered any number of incorrect ways - what you are defining isn't headspace - we have a handy term for that,
head clearance

quote:

Originally posted by eagle27:
and this is what the focus is on trying to minimise.

in all honesty, we are trying to normalize to a minimum - if we minimized head clearance to zero, then temp differences could cause the brass to not fit

quote:

Originally posted by eagle27:
Gee how many of us have checked for excessive "headspace" by sticking circles of aluminium foil on the bolt face until we get a snug fit, we don't stick it on the bloody case shoulder.

why, you've just expressed gauging headspace - taking a thing, and probing for depth -- not precisely measuring it, btw,
but feelings for it

quote:

Originally posted by eagle27:
Why were different bolt heads made available for the SMLE, they didn't make cartridges with thicker or thinner heads or push out the shoulders on batches of cartridges to reduce headspace, they just changed the bolt head to take up the space.

again, you are measuring the GUN -
this is really that simple - you are checking the headspace OF THE GUN -- how many of us have neck sized to overcome a long chamber? we aren't changing the headspace by this, we are loading to the gun

quote:

Originally posted by eagle27:

What happens when a break open gun goes off the face, how the headspace is technically measured doesn't matter diddly squat, the gun has to be brought back on face, nothing to do with the chamber dimensions or cartridge.

we disagree - when it goes off face,
a couple things happen, one is that the HEADSPACE is changed, due to mechanical changes to the FIREARM, not the case, and another is that it may be unsafe to fire perfected sized cases, due to excessive headspace or not locking and being unsafe .. zero changes to the cart, all changes are on the gun

quote:

Originally posted by eagle27:
That little gap that has developed between the barrels/cartridge head and breech face has to be taken out.

the mechanical changes to the firearm, resulting in excessive headspace, has to be corrected to make it safe to fire the exact same carts is was designed to shoot - you haven't changed the cart

quote:

Originally posted by eagle27:

Why do you think there is so much confusion over the term headspace?

because people are invested in their (mis)understanding of the erm

quote:

Originally posted by eagle27:
Because some go into so much detail of it being measured from a datum point in the chamber or on the case and when the cartridge is fired it expands and contracts and blah blah blah blah

see, it's not hard at all

quote:

Originally posted by eagle27:

while the poor tyro gun owner and reloader scratches his head and wonders what the hell language you are speaking.

i wonder why they are reloading if they don't know these terms

quote:

Originally posted by eagle27:
Just think head - space/gap/clearance/foil thickness/blade of grass stuck on breech face, piece of brass stuck on bolt face, broken finger nail in breech, anything but not datum bloody points

it's really simple -

Excellent rendering Bigrdp51 and illustrates the poignant point that one picture is worth a million words...as this tome is proving.


REMEMBER...HEADSPACE is a measurement of the CHAMBER...the only thing about a cartridge is the SURFACE in the CHAMBER where a cartridge SEATS...a cartridge DOESN'T need to be present, NOR a gauge to fulfill the definition(a gauge is just easier to use)...just a breach face, a point in the chamber for a seating point and a numerical measurement..

AND...when I say ZERO headspace there is ALWAYS that amount of HEAD CLEARANCE for the CARTRIDGE...again defined by SAAMI. Ya'll are arguing semantics and dis-remembering the actual definition or aren't quite to the understanding part....or maybe just stirring the pot. WHO IS GOING TO BLINK FIRST??????

Seems like everyone is also FORGETTING that SAAMI is a standard followed by all the signators...bullet makers, die makers, reamer makers, brass makers and weapon makers...so that manufacturing tolerances, or IN-TOLERANCES wont muck up the works. Even with those standards in place there is always a certain percentage of fowl-ups that cause the re-dazzz.

Good Hunting

Amidst all the intellectual, technical "masturbation", we now know that we size cases to minimise head clearance so that the case (almost) matches head space. The goal is that all cases can be sized uniformly for accuracy and long life.

So to answer your original questions please see below

quote:

Originally posted by lucy11:
Hello,

Can true headspace be determined when a case is only fired once in the chamber of the same rifle? No, the case measurement will give you less than head space because of brass spring back. You can assume safely that the case measurement gives you minimum head clearance IF you measure the case with a tool like the hornady tool.

I've heard that it may take 2 or 3 firings before the headspace of a case can be accurately measured to the chamber. Not true. The case measurement can vary due to spring back of brass and if you used the FL die to partial neck sizing, thus moving the shoulder forward for a crush fit in chamber.

If that is a true statement, can I use the Hornady Neck Sizing Die to just neck size the first few fired cases while waiting for "true" chamber headspace to be reached then use the dies full potential to neck size and bump the shoulder as needed? Not necessarily true or false. Too many variables such as brass spring back, variable pressure of reload, and if you are using just a neck sizing die rather than a FL die backed off.

Any input is greatly appreciated.
Just neck sizing may not always give you a concentric neck, which is vital for good accuracy. Check ammo run out and see if it wobbles. Just eyesight can pick up 15 thou variance in concentricity. Using a backed off FL die along with the Hornady gauge will give you exactly the same dimension brass every single time until eternity. If after say 10 reloads you find some chambering resistance, then you probably have neck THICKNESS issue!

Thanks
Mike

Some of you people need to buy a British .303 Enfield rifle and play with your bolt heads until you nearly go blind.

Then you might understand the word headspace. Military Enfield headspace is min .064 to max .074 and the rifle below has had the headspace set from .058 to .084 and checking the effect on case stretching.

Again, Biggy...excellent representation again including the incipient head separation notch. If that doesn't clear up the mud NOTHING WILL. You sure have some neat drawing tools to play with.

I've played with a few of those ungodly things...turned one into a 458 American...left the Jungle Carbine as is and the #4 is just a wall hanger, more or less...but I gave designs on doing a 50 cal something to it. The Carbine isn't too bad so I just adjusted the gapitis out with the sizer die/Redding Comp shell holders and get 7-8 reloads per case. The barrel and chamber aren't the best either so I just bang away at rats and squirrels up close with whatever bullets I find cheap.

Good Hunting

At one point in time I had a .303 Enfield. I could get 2 reloads out of once fired brass.

quote:

Originally posted by craigster:
At one point in time I had a .303 Enfield. I could get 2 reloads out of once fired brass.

I use a Canadian method to fire form my .303 cases. You slip a small thin rubber o-ring around the case and it forces the case against the bolt face.



Thereafter you only neck size the case and let the case headspace on its shoulder.



I use reduced loads of SR4759 or Trail Boss to form the cases using 100 grain .312 pistol bullets.

Now, that O ring idea for the .303 is the only clear, good, valid, idea to come out of this entire thesis of headspace comments.

Funny thing about headspace, rim thickness and all those things...I can shoot 45-70 round in my SMLE 458 American also...the 45-70 rim just fits in that "HEADSPACE/HEAD CLEARANCE OR WHATEVER" space and BOTH cartridges basically conform to standard SAAMI specs....!!!!!

I read somewhere, o some British SMLE information forum about the "O" ring thing but never tried it. I basically did the old false shoulder, size and fit thingy to get there.

There it is again...a few pictures totally stomp on our inability co communicate clearly.

I gotta try that "squirrel" load...and the "O "ring method to fire form the rest of my new 303 brass...DEFINITELY CHEAPER and quicker.

Good Hunting

That is just an accident from how your 458 was chambered in the Enfield; i.e., how much of the belted case is protruding from the barrel face. Nothing to do with SAAMI tolerances.

quote:

Originally posted by bigrdp51:

quote:

Originally posted by craigster:
At one point in time I had a .303 Enfield. I could get 2 reloads out of once fired brass.

I use a Canadian method to fire form my .303 cases. You slip a small thin rubber o-ring around the case and it forces the case against the bolt face.



Thereafter you only neck size the case and let the case headspace on its shoulder.



I use reduced loads of SR4759 or Trail Boss to form the cases using 100 grain .312 pistol bullets.

Excellent post, thank you !

quote:

Originally posted by dpcd:
Now, that O ring idea for the .303 is the only clear, good, valid, idea to come out of this entire thesis of headspace comments.

And

quote:

Originally posted by Craigster:
Excellent post, thank you !

Agree totally. I just keep learning.

quote:

Originally posted by dpcd:
Now, that O ring idea for the .303 is the only clear, good, valid, idea to come out of this entire thesis of headspace comments.

except for the handy term of clearance -- if we could only get it to catch on

quote:

Originally posted by jeffeosso:

quote:

Originally posted by dpcd:
Now, that O ring idea for the .303 is the only clear, good, valid, idea to come out of this entire thesis of headspace comments.

except for the handy term of clearance -- if we could only get it to catch on

Totally agree Jeffeosso and I too regard our discussion as warm and friendly, sometimes frustrating Your last post has been the purpose of my posts right from the start. Forget about what headspace technically refers to, just think of it as that gap, that everyone now seems to at least agree on, called "head clearance" as the only focus needed so a cartridge case is made or altered to form a snug fit in the chamber with no, or very minimal, head clearance.

The O'ring concept shows it all, the head clearance was worked on with an o'ring taking the gap out for the first firing and the case shoulder is moved forward for subsequent firings. The technical headspace measurement has not been changed i.e. we have not worked on or changed headspace. In the SMLE action the headspace measurement would only change if a longer or shorter bolt head was used.

Likewise for belted bottle neck cases the technical headspace measurement (forward edge of belt recess to bolt face) is never changed, can't be unless the chamber is recut, but excessive head clearance can be taken up by neck sizing or partially F/L resizing to leave the shoulder where it has blown forward. Even for a first firing with these cases the bullet can be seated longer to engage the rifling and set the case head back to the bolt face so the all important case head area is not stretched.

All rather boring and easy if we would only just use the KISS principle, and that is not aimed at any one, it is a common term we apply to many situations and even ourselves sometimes.

Craigster

What is the need for using a bullet in the first place?

I have a bit of experience in fire forming cases. I did a lot for the 280 Ack Imp 20 years ago when I had to fire form 280 Rem brass. I loaded standard bullets and used them on the range.

In recent years I have been fire forming for my 9.5X57 Mannlicher Schoenauer. Factory cases are not available. I got some 35 Whelan trimmed cases from Buffalo Bore. I am also fire forming 9.3X57 Norma brass as the head space is the same but taper is more.

Instead of shooting expensive 375 bullets, I just loaded 20 gr of shotgun powder and stuffed the cases with 2 squares of toilet paper. All the cases are perfectly formed now.



Craigster -

quote:

I use reduced loads of SR4759 or Trail Boss to form the cases using 100 grain .312 pistol bullets.

quote:

Originally posted by Nakihunter:
Craigster

What is the need for using a bullet in the first place?

I have a bit of experience in fire forming cases. I did a lot for the 280 Ack Imp 20 years ago when I had to fire form 280 Rem brass. I loaded standard bullets and used them on the range.

In recent years I have been fire forming for my 9.5X57 Mannlicher Schoenauer. Factory cases are not available. I got some 35 Whelan trimmed cases from Buffalo Bore. I am also fire forming 9.3X57 Norma brass as the head space is the same but taper is more.

Instead of shooting expensive 375 bullets, I just loaded 20 gr of shotgun powder and stuffed the cases with 2 squares of toilet paper. All the cases are perfectly formed now.



Craigster -

quote:

I use reduced loads of SR4759 or Trail Boss to form the cases using 100 grain .312 pistol bullets.

Not my quote. It belongs to bigrdp51.

Sorry mate!